Embodiments of the invention relate to using Transparent Interconnection of Lots of Links (TRILL) protocol in edge virtual bridging (EVB) environments, and in particular, automatically configuring a TRILL device port in an EVB enabled network environment.
Edge Virtual Bridging (EVB) (IEEE 802.1Qbg) allows for two possible modes of operation for hypervisor host-internal switches: Virtual Ethernet Bridge (VEB) and Virtual Ethernet Port Aggregator (VEPA). VEB mode allows virtual machine (VM) network traffic to be switched internally to the hypervisor host whenever the network traffic is between VMs on the same host. VEPA mode allows the host-internal switch to acts as a port aggregator such that all VM traffic is first passed to the physical switch for processing. The physical network switches must support reflective relay (RR) in order to allow the VEPA mode of operation.
TRILL combines the advantages of bridging and routing. Bridges (e.g., devices that perform layer-2 forwarding) may transparently connect multiple links to create a single local area network. The topology on which traffic is forwarded in a bridged network must be a tree to prevent loops. Forwarding the traffic over a tree may cause traffic concentration on the links that correspond to the tree edges, leaving other links completely unutilized. Unlike bridges, Internet Protocol (IP) routers (e.g., devices that perform IP forwarding) do not need to create a spanning tree for forwarding traffic. Routers that forward IP traffic require more configuration than bridges, and moving nodes in an IP network requires changing the IP address of the nodes. Each link in an IP network is associated with an address prefix, and all nodes on that link must have that IP prefix. If a node moves to another link that has a different IP prefix, the node must change its IP address.
A TRILL network includes “routing bridges” (RBridges) which route packets, but like bridges, learn layer-2 address locations through receipt of packets. Since packets are routed, packet forwarding is not limited to a spanning tree. Also, since a hop count is included in a TRILL packet, packets do not circulate forever in the network in the presence of loops. Since the layer-2 address locations are learned, a TRILL network allows IP nodes to move from one link to another in the network without any restrictions.